Solve the problem. A retired couple buys a new recreational…

Solve the problem. A retired couple buys a new recreational vehicle (RV) for $50,000. They make a down payment of $13,000 and finance the balance at 9.0% APR over 60 months. Their monthly payments are $768.06. Before making the 30th payment, the couple decides to pay the remaining balance on the loan. How much interest will the couple save? (use the actuarial method)